Or ICH will continue its cycle. I am surprised the blue hippo tang wasn't the first to get ICH. Your tank is overstocked with fish that do no belong in a reef tank. Do some research on how far any tang swims in a given day. Yes people keep them and LFS continue to sell them but unlike most reef inhabitants the tang (any species) moves allot. They swim many miles a day. You might win this battle with ICH but it will be back. Personally I think it is cruel to keep a Tang of any species in a tank.